One known construction of coulter disk vertical tillage implements having toolbar devices which are angularly adjustable relative to a forward working direction comprises U.S. Pat. No. 8,746,361 by Great Plains Manufacturing, Inc. Each toolbar is supported on the implement frame for pivotal adjustment about a vertical pivot axis at an intermediate location offset towards one side of the toolbar requiring additional support for the toolbar using guide plates in sliding contact at an intermediate location along the toolbar spaced from the pivot axis. The pivot and guide plate configuration provide limited support against torsional deflection of the toolbar however.